Hi Guys, We have a chevrolet 1988 G20 Van ( Coachmen Camper van ) built. we have a few problems that we need help to find out what it could be. maybe it is a common problem
1. ac dont activate, starts and then shut off within a second or so ( its filled , have pressure )
2. vents only work on defroster ,
3 . our fan blowed fuses instantly, found that. leaves,etc in the fan-box bottom cleaned that and it blows at all speed

we really hope for tips and ideas

thank you guys

 

1) What is the static pressure? Engine off, it should mirror the engine bay ambient temperature within a few degrees. More than about 10 degrees difference indicates the system is over or undercharged.

2) Is the mode door (switches between defrost, panel vents and floor) cable or vacuum operated? If vacuum, check that the supply tube from the engine bay is connected (typically routed through the firewall near the accumulator).

3) Not sure what you’re asking here.

 

On such a dinosaur of a van, I wouldn't be surprised if the vacuum lines disintegrated. Plastic/rubber doesn't last, and the heat kills it quicker.

 

They are vacuum, I pulled a head off one last week. The only cable is for the temperature door.

If the fan had leaves in it, I wouldn't be shocked if there's more elsewhere in the ducts.

 

If you have not already, check the blower motor resistor. When these guys go out the fan will only (usually) blow in defrost mode. It's some crazy idea regarding safety. Usually run between 20 to 40 bucks. I had a similar issue a while back. I blamed it on my son's friends messing with it 😬.

Good luck

 

Typically a bad resistor will only allow the fan to blow on high speed.

The default position for the mode door actuator is defrost, so if the actuator fails (or vacuum is lost) it only blows on defrost to keep the windshield clear during low visibility or winter weather.